Method of treating solid materials.



No. 802,620. PATENTED OCT. 24, 1905. K.-BIRKELAND & S, HYDE, METHOD OF TREATING SOLID MATERIALS.

APPLIUATION FILED SEPT,1, 1904. V 2 SHEETS-SHEET 1 Fig.1.

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Anoazw. a, unmm m, PHOYO-UYHOGRAPHERS. wLsmm'oN. I)v a No. 802,620. PATENTED 00124, 1905. K. BIRKELAND & S. EYDE. METHOD OF TREATING SOLID MATERIALS.

APPLIOATION FILED SEPT, 1, 1904.

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5 I 1 III/Mi 0 0 Inge 31 3b 7's. MW @MM KRISTIAN BIRKELAND AND SAMUEL EYDE, OF CHRISTIANIA, NORNVAY.

METHOD OF TREATING SOLID MATERIALS.

Specification of Letters Patent.

Patented Oct. 2 1, 1905.

Application filed September 1,1904. Serial No. 222,964.

To all whmn it nuty concern:

Be it known that we, KRISTIAN BIRKELAND and SAMUEL EY1)n,subjects of the King of Norway and Sweden, residing at Christiania, Norway, have invented certain new and useful Improvements in the Method of Treating Solid Materials; and we do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same, reference being had to the accompanying drawings, and to figures of reference marked thereon. which form a part of this specification.

Our invention relates to an improved method of treating solid materials for the purpose of subjecting the same to a reduction or oxidation process.

The principal feature of our method consists in submitting the materials to the effects of an electrical are, which is made to fill the interior of a furnace in adisk shape in a wellknown manner by aid of a strong magnetic field.

Our invention may, for example, be advantageously used for the reduction of ores. This is accomplished by letting the ores, preferably, but not necessarily, reduced to a powdered state and mixed or not, as the case may be, with coal, fall through the furnace-cham- 'ber. .This chamber is so arranged that the air is excluded when necessary and may be supplied with reducing or with neutral gases. The materials may also be introduced into the furnace in any other suitable wayfor instance, through channels provided in the electrodes or alongside of the same. I

In the accompanying drawings is shown a practical form of a furnace adapted for bringing this method into execution.

Figure 1 is a front view of the furnace; and Fig. 2, a vertical section of the same on line A B, Fig. 1.

This furnace consists of two walls 1 and 2, of fireproof insulating material, placed near each other, and which walls, together with the end walls 3 and 4; and the roof 5, inclose a narrow but long and lofty furnace-chamber. Through the end walls 3 and 4 the adjustable electrodes 6 and 7 reach into the said chamber, so as to leave between their points a short adjustable space lying in a line connecting the magnet-poles 8 and 9 of the vertically-arranged electromagnet 1O 11 12. The polepieces 8 and 9 are provided with a number of radially-arranged iron projections or arms 13 14 for spreading the magnetic lines of force as far as possible out from the middle of the furnace.

The electromagnet 1O 11 12 is of great di mensions. The voltage required for the maintenance of magnetism may, however, be small. For a furnace calculated for thirty to forty kilowatts we may apply a magnet-current of 0.4 kilowatts.

15 is a feeding device by aid of which the pulverized material is fed into the furnace at the upper end of the same in a thin even stream. It passes along or through the are spread in the furnace for the whole extension of the same and hereby will eventually be wholly or partly evaporized. At the bottom of the furnace there are provided exit-hoppers 16, with which hoppers are connected tubes 17 for the exit of the gases generated in the furnace. The solid particles fall down through the inclined passages 18 and are gathered in the chamber 19.

The electrodes may eventually be made hollow and used for introducing gasesfor instance, hydrogen, illuminating-gas, or other reduction gases. The electrodes may be made of coal, as the reductiongases will protect them against combustion. One may, however, also use metal electrodes.

Together with the pulverized raw material we may also introduce pulverized coal. In the above form the electrodes are arranged horizontally; but they may also advantageously be arranged vertically. The material to be treated may in this latter case be fed into the furnace from above on each side of the electrodes and pass along the same without being impeded by the same.

Compared with other electrical furnaces for similar purposes the furnaces here referred to possess the advantage of the material to be treated being in suspension in the chamber, where it is subjected to the action of the electrical arc. The material will here have to pass through a relatively long space, being all the time exposed to an intense heating effeet. This will greatly add to the effectivity of the furnace. This construction also possesses the advantage of the working conditions of the process being more easily controlled, and suitable gases, &c., are more easily introduced.

The gas atmosphere in the furnace may of course eventually be obtained by the evaporization of materials introduced into thefurnace. The solid materials to be treated need not always be fed into the furnace in pulverized state, but may also be introduced in form of briqueted bars pressed from ore and coal or other materials. If the furnace is to be used for oxidation, roasting, or similar purposes, suitable gases, as air, may be introduced into the same.

Having now described our invention and in what manner the same is to be performed, we declare that What We claim is- 1. The method of treating solid materials, which consists in forming an arc in a suitablyclosed chamber, spreading the arc over the chamber by magnetic flux transverse of said are, and causing the solid material to pass through the arc and be acted upon by the arc while in suspension in the are, substantially as described.

2. The method of treating solid materials, which consists in forming an arc in a suitablyclosed chamber, spreading the are over the chamber by a magnetic flux transverse ofsaid arc, causing the solid material to fall through the arc and be acted upon thereby while in suspension in the are, substantially as described.

3. The method of treating solid materials, which consists in forming an arc in a suitablyclosed chamber, magnetically spreading the are over the chamber, causing the material to pass through the spread arc, and maintaining in the are suitable gaseous atmosphere capable of reacting on the solid material in the are, substantially as described.

4. The method of treating solid materials, which consists in forming an arc in a suitablyclosed chamber, producing a magnetic field around the chamber to spread the are over the chamber, introducing the solid material into the chamber at the center of the are near its point of formation, substantially as described.

5. The method of treating solid materials, which consists in forming an arc bet-ween vertically-disposed electrodes in a suitably-closed chamber, producing a magnetic lield around the chamber to spread the are over the chamber laterally to the electrodes and causing the material to pass through the spread arc in a direction parallel to the electrodes.

6. The method of treating solid materials, which consists in forming an arc in a suitablyclosed chamber, magnetically spreading the are over the chamber, causing the material to fall through the spread arc and introducing into the are a suitable gas near its point 01'' formation capable of reacting with the material, substantially as described.

7. The method of treating ores, which consists in forming an arc in a comparatively narrow chamber, producing a magnetic field around the chamber to spread the arc and dropping finely-ground ore through the spread arc, and introducing into the arc and magnetic lield a suitable gas capable of reacting with the ore, substantially as described.

8. The method of treating ores, which con sists in forming an arc in a comparatively narrow chamber, producing a magnetic field around the chamber to spread the arc, introducing into the arc and magnetic field and through the electrodes a suitable gas, dropping the material through the chamber and arc, and withdrawing both gaseous and solid products of the reaction from the bottom of said chamber, substantially asdescribed.

In testimony that we claim the foregoing as our invention we have signed our names in presence of two subscribing witnesses.

KRISTIAN BIRKELAND. SAMUEL EYDE. Witnesses:

HENRY BORDEWIOH', AUG. OLSEN. 

